The detailed hydrographic network shows all the flow channels visible on the territory of 12 MRCs in Montérégie. This photo-interpretation project was carried out on a scale varying from 1:500 to 1:2000, using orthophotos (spring 2020 at 20 cm resolution for the territory excluding CMM and spring 2018 at 10 cm resolution for the territory in CMM) and the shaded relief derived from LiDAR data (2008 to 2020). The project was carried out as part of the Regional Program for the Acquisition of Data on Wetlands and Water Environments (PRADMHH) and was funded by the Regions and Rurality Fund (FRR) of the Montérégie regional department of the MAMH.**This third party metadata element was translated using an automated translation tool (Amazon Translate).**